fix: exit earily on empty list in map and parallel#324
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Fix crash when calling context.map() or context.parallel() with empty list. Previously, empty executables caused ThreadPoolExecutor to be initialized with max_workers=0, raising ValueError. Add early return in ConcurrentExecutor.execute() to immediately return empty BatchResult when no items need processing. This avoids creating ThreadPoolExecutor with invalid worker count and matches expected behavior where empty input produces empty output. Add regression test to verify empty list handling works correctly. closes #323
ayushiahjolia
approved these changes
Mar 9, 2026
ParidelPooya
approved these changes
Mar 9, 2026
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Description of changes:
Fix crash when calling context.map() or context.parallel() with empty list. Previously, empty executables caused ThreadPoolExecutor to be initialized with max_workers=0, raising ValueError.
Add early return in ConcurrentExecutor.execute() to immediately return empty BatchResult when no items need processing. This avoids creating ThreadPoolExecutor with invalid worker count and matches expected behavior where empty input produces empty output.
Add regression test to verify empty list handling works correctly.
Issue #, if available:
closes #323
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